Select Code to Download

Select or download this

use Config     qw( %Config );
use List::Util qw( max );

my $max = max( ~0+1, eval( $Config{ nv_overflows_integers_at } ) );

Select or download this
```
[+/-]1._____..._____ * 2**____
```

Select or download this

     __52 bits__
    /           \
...
  1.00000...000001 * 2**53    But we have limited number of bits
--------------------------
  1.00000...00000  * 2**53    Original large power of two

Select or download this

$ perl -MB=svref_2object,SVf_IVisUV,SVf_NOK -e'
   $i = 0;
...
      :                            "IV\n";  # Signed int
'
IV

Select or download this

$ perl -MConfig -MB=svref_2object,SVf_IVisUV,SVf_NOK -e'
   $i = hex("7F".("FF"x($Config{ivsize}-2))."FD");
...
IV 2147483647            <-- 2**31 - 1  Largest IV
UV 2147483648
UV 2147483649

Select or download this

IV 9223372036854775806
IV 9223372036854775807   <-- 2**63 - 1  Largest IV
UV 9223372036854775808
UV 9223372036854775809

Select or download this

$ perl -V:[in]vsize
ivsize='4';   # 32-bit integers
nvsize='8';   # 64-bit floats

Select or download this

$ perl -V:[in]vsize
ivsize='8';   # 64-bit integers
nvsize='8';   # 64-bit floats

Select or download this

$ perl -MConfig -MB=svref_2object,SVf_IVisUV,SVf_NOK -e'
   $i = eval($Config{nv_overflows_integers_at}) - 3;
...
NV 9007199254740991                 Precision required as a float:
NV 9007199254740992  <-- 2**53      1 bit
NV 9007199254740992  <-- 2**53 + 1  54 bits, but only 53 are available

Select or download this

$ perl -MConfig -MB=svref_2object,SVf_IVisUV,SVf_NOK -e'
   $i = hex(("FF"x($Config{ivsize}-1))."FD");
...
UV 18446744073709551615  <-- 2**64 - 1  Largest UV
NV 18446744073709551616  <-- 2**64      1 bit of precision required
NV 18446744073709551616  <-- 2**64 + 1  65, but only 53 are available